Holding Tank Heating System

ABSTRACT

A portable toilet satellite station comprising an enclosure having a front wall, rear wall, side walls and a roof. The enclosure further having an inside area at least partially defined by the front wall, rear wall, side walls and the roof. The portable toilet satellite station further including a toilet having a holding tank. The portable toilet satellite station further including a heating system in communication with the holding tank. The heating system is capable of producing warmed air that can be directed through the heating pipe and into the holding tank and preferably also the inside of the enclosure to warm a user.

RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application Ser.No. 61/030,274, filed Feb. 21, 2008, entitled “Holding Tank HeatingSystem,” the disclosure of which is hereby incorporated by reference.

BACKGROUND OF THE DISCLOSURE

1. Field of the Invention

The present invention relates generally to heating systems for sewageholding tanks. Particularly, the present invention relates to heatingsystems for portable toilet satellite stations or above ground sewageholding tanks. More particularly, the present invention relates to aheating system for a portable toilet satellite station holding tank thatwarms the holding tank and the inside area of a portable toiletsatellite station to additionally warm users.

2. Description of the Related Art

A portable toilet, also known as a port-a-potty, is a modern, portable,self-contained outhouse typically manufactured of molded plastic oftenused as a temporary toilet for construction sites, parks, outdoor eventsand the like where no sanitation facilities exist.

Typical portable toilets are large enough for a single occupant. Theyare held upright by a base and the weight of the liquid in the holdingtank at the bottom but are usually also secured to the ground to preventhigh winds from blowing them over. Some portable toilets include both aseated toilet and a urinal and possibly a sink. Most include lockabledoors, ventilation near the top, and a stovepipe vent for the holdingtank.

The collection of sewage in the holding tank must be kept in generallyliquid form in order to efficiently and hygienically remove the sewagefrom the holding tank for disposal. A vacuum truck sucks the sewage outfrom the holding tank and then the sewage is transported to be disposedof. Keeping sewage at a temperature above freezing can be particularlychallenging in areas where the temperature outside is below freezing.

One known method of preventing liquid in the holding tank from freezingis adding salt brine to the tank. Salt brine is a mixture of salt and amixing agent such as water. Using salt brine is labor intensive becauseof the need to store enough salt and to mix the brine in effectiveproportions. It also requires that the disposal trucks used to transportthe raw sewage from the portable toilet be washed down daily such thatthe salt is washed off so it will not corrode the components of thetruck that come in contact with the salt brine solution, usually thepump and tank.

A second known method of preventing liquid in the holding tank fromfreezing is to add methanol to the holding tank. Methanol is a petroleumproduct which has anti-freeze characteristics. Being a petroleumproduct, the cost of methanol is increasing daily. In addition, it is anexplosive liquid that must be carefully mixed. If the portable toiletowner is dumping the raw sewage in a rural environment, methanol has anegative effect on environmental quality and may be considered apollutant. The disposing of any methanol, wherever, has a negativeenvironmental effect, as city sewage plants cannot remove this pollutantin their refining processes.

Adding traditional anti-freeze to the tank is a third method ofpreventing holding tank freezing. Traditional anti-freeze is alsoexpensive and is often cost prohibited. In addition, this methodrequires extra effort to dispose of legally.

Government regulations often additionally require that in the workplace,often at construction sites, portable toilets be heated. To heat theportable toilets, many employers rely on known portable space heaters;however, these are easily removed from the portable toilet andtherefore, the space heaters are often missing for various reasons. Thisprovides for a time consuming and costly responsibility of continuing tomaintain government regulatory standards.

The present invention overcomes problems associated with the relatedart.

SUMMARY OF THE INVENTION

The present invention relates to a portable toilet satellite stationincluding an enclosure having a front wall, rear wall, side walls and aroof, the enclosure further having an interior at least partiallydefined by including the front wall, rear wall, side walls and the roof.The portable toilet satellite station preferably further includes a doorin the front wall and a toilet located within the enclosure. In somepreferred embodiments, the portable toilet satellite stationadditionally includes a sink that drains into the holding tank. Thesink's source of water can be a water tank located above the sink.

The toilet includes a holding tank preferably having a vent leadingoutside of the enclosure to vent gases produced by sewage stored in theholding tank. To generally prevent freezing of the sewage within theholding tank and water within the water tank, the portable toiletincludes a heating system, such that the holding tank can be heated. Inthe most preferred embodiments, the heating system further includes aninterior vent that at least partially directs heated air produced by theheating element into the interior of the enclosure.

In some preferred embodiments, the heating element is an electric coilheater placed within a heater pipe. An example of a suitable electriccoil heating element is disclosed in U.S. Pat. No. 6,869,533 (Norgaard).

These and various other advantages and features of novelty whichcharacterize the present invention are pointed out with particularity inthe claims annexed hereto and forming a part hereof. However, for abetter understanding of the invention, its advantages and objectsobtained by its use, reference should be made to the drawings which forma further part hereof, and to the accompanying descriptive matter, inwhich there is illustrated and described a preferred embodiment of thepresent invention.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, in which corresponding reference numerals and lettersindicate corresponding parts of the various embodiments throughout theseveral views, and in which the various embodiments generally differonly in the manner described and/or shown, but otherwise includecorresponding parts;

FIG. 1 is a perspective view of a portable toilet satellite station 10of the present invention;

FIG. 2 is a partially exploded and partial cutaway view of the portabletoilet satellite station 10 of FIG. 1 illustrating an interior area 24and the preferred configuration and installation of a heater system 40;

FIG. 3 is a partial, cutaway view of the heater system 40 of FIG. 2;

FIG. 4 is a partial cutaway schematic view of an alternate embodiment ofthe present invention illustrating an above-ground holding tank system100 having a heating system 140, preferably, generally similar to theheater system 40 of FIGS. 2-3; and

FIG. 5 is a cross-sectional view of the heater pipe 42 of FIG. 3 asviewed along line 5-5.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 illustrates a preferred portable toilet satellite station 10. Theportable toilet satellite station 10 includes an enclosure 12 having afront wall 14 having a door (not shown), rear wall 18, side walls 20 a,20 b and a roof 22. The enclosure 10 further includes an inside area 24at least partially defined by the front wall 14, rear wall 18, sidewalls 20 a, 20 b and the roof 22. The inside area 24 is generally thearea in which a user would move about when using the satellite station10. Within the inside area 24, a toilet 26 and, optionally, a urinal(not shown) are located. The toilet 26 and urinal are interconnected toa holding tank 28 having a tank interior 30 in which sewage (not shown)is stored until it can be disposed. In preferred embodiments, theholding tank 28 contains a deodorizing liquid (not shown) as is commonlyused. The preferred holding tank 28 is vented with a vent pipe 32extending upwardly from the holding tank 28 and then outside of theenclosure 12.

Portable toilets are most commonly used outside. In colder climates, thedeodorizing liquid and sewage within the tank interior can freeze, thusmaking it very difficult to dispose of and also indicating that thetemperature within the enclosure is quite cold, uncomfortable for usersand potentially in violation of government standards. The preferredportable toilet satellite station 10 includes a heating system 40 toselectively heat the holding tank 28 and generally prevent freezing ofthe liquid and sewage within the tank interior 30. In preferredembodiments, the heating system 40 includes a heater pipe 42 andgenerates heated air that is directed through the heater pipe 42 andinto the tank interior 30 to warm the contents of the holding tank 28.In preferred embodiments, the heated air is also directed into theinside area 24 of the enclosure 12 by venting the heated air through atransverse aperture or interior vent 44 in the heater pipe 42. Preferredembodiments warm the contents of the tank interior 30 as well as warmingthe inside area 24 of the enclosure 12 to increase user comfort as isoften required by government regulations. In addition, by heating theinside area 24 of the enclosure 12, a water holding tank 72 for a sink74 will further be prevented from freezing.

A preferred heating system 40 is illustrated in FIGS. 2-3. The heatersystem 40 includes a heating element 50, in this embodiment, an electricheater coil 50, which can be inserted within the heater pipe 42. Anexample of a similar electric coil heating element is disclosed in U.S.Pat. No. 6,869,533 and U.S. application Ser. No. 11/951,894 (Norgaard),the disclosures of which are herein incorporated by reference. It isnoted that this type of a heating element is preferred and otheralternative heating elements and devices for producing heated air areconsidered within the scope of the invention.

The heater pipe 42 is then inserted into or otherwise operativelysecured to an aperture 29 in the holding tank 28. The heating system 40preferably further includes a blower assembly 44 having a motor 46Adriving blower 46B located above the heating element 50 for directingand circulating warm or heated air down through the heater pipe 42 andinto the holding tank 28 and, preferably, into the inside area 24 of theenclosure 12. In preferred embodiments, the heating system 40 producesabout 50 cfm output warm air flow. For that purpose, the heater pipe 42includes an air intake 43 above the blower 46B. Preferably, the airintake includes a screen or filter 48 and is arranged and configuredsuch that tampering or insertion of objects into the heater pipe 42proximate the blower 46B is difficult (see also, FIG. 5). Additionaltampering prevention methods can include fastening the heater pipe 42 toat least one wall 18, 22 a, 22 b of the enclosure 12 with screws orrivets 5 to make removal of the heating pipe 42 difficult.

The heating system 40 preferably includes a temperature control unit 52connected to the exterior of the heater pipe 42 with at least oneretaining element 54. The temperature control unit 52 activates theheater element 50 and blower motor 46A. A removable cover 56 on thecontrol unit 52 permits access to the wiring and controls for blowermotor 46A and heating element 50. A temperature control thermostat (notshown) can be housed within the control unit 52, and may be adjusted tothe desired temperature to be maintained within the holding tank 28 orinside area 24 so as to generally prevent freezing of the holding tankcontents as well as to warm the inside area 24 of the enclosure 12.

The thermostatic control unit 52 could optionally further include atemperature sensor 58 located near the heated air output end 43 of theheating pipe 42 by output coupling 41 A. Operation of the heater element50 and the blower assembly 44 may be regulated by the sensor 58 toachieve the desired temperature of warm air discharged through outputcoupling 41 A. Because many of the elements may be made of plasticmaterial, such as the heater pipe 42, it is preferred to have the heatoutput sensor 58 to prevent overheating and resultant melting of suchelements. In certain embodiments, this temperature is about 150 to about160 degrees F.

The heating system 40 of the present invention is preferably powered byconnecting an electric cord 80 extending out of the temperature controlunit 52 to an extension cord 81 having access to a source of electricity(not shown). It will be understood that alternative sources of powersuch as battery, propane, sun or wind power, for example, are consideredwithin the scope of this invention.

In preferred embodiments, the portable toilet satellite station 10includes a sink system 70 for users to wash up. The sink system 70 caninclude a sink bowl 74 having a faucet 75. The sink system 70 furtherincludes a water tank 72 interconnected to the faucet 75 and providingthe source of water. Waste water drained from the sink bowl 74 isdirected down into the holding tank 28 via a conduit or drainage pipe76. As previously discussed, the heating system 40 of the presentinvention warms the water tank 72 by directing warm air into the insidearea 24 of the enclosure 12 to ensure the water tank 72 does not freezeand the sink system 70 remains operable.

One alternate embodiment of the present invention is illustrated in FIG.4. This embodiment is an above-ground holding tank system 100. Theabove-ground holding tank system 100 includes a restroom 112, in atrailer or the like, having a toilet 126 and a sink system 170. Waste istransferred from the toilet 126 and the sink system 170 to anabove-ground tank 128 with respective pipes 129. In cold weather, theabove-ground tank 128, just like the portable toilet holding tank 28, issusceptible to freezing. The preferred above-ground holding tank system100 preferable includes an aperture 127 on the tank 128 through which aheating system 140 of the present invention can be secured. The heatingsystem 140 directs warm air down towards and into the above-groundholding tank 128. The heating system 140 of FIG. 4 is preferably similarto the heating system 40 of FIG. 3. The heating system 140 preferablyincludes a goose-neck air intake section 143 for drawing in cold outsideair to be warmed and directed into the above-ground holding tank 128.The warm air prevents sewage S within the above-ground tank 128 fromfreezing and can be vented through a roof vent 132.

Although the preferred embodiments of the present invention have beendescribed herein, the above description is merely illustrative. Furthermodification of the invention herein disclosed will occur to thoseskilled in the respective arts and all such modifications are deemed tobe within the scope of the invention as defined by the appended claims.

1. A portable toilet satellite station comprising: an enclosure having afront wall, rear wall, side walls and a roof, the enclosure furtherhaving an inside area at least partially defined by the front wall, rearwall, side walls and the roof; a toilet located within the inside areaof the enclosure, the toilet including a holding tank having a tankinterior; a vent pipe interconnecting the tank interior to outside ofthe enclosure; and a heating system including a heating pipe incommunication with the holding tank, the heating system further havingheating element in air flow communication with the heating pipe suchthat air can be directed through the heating pipe and into the holdingtank; wherein the heating element can produce warm air; wherein theheating system is constructed and arranged to direct at least a portionof the warm air into the inside area of the enclosure to warm the insidearea.
 2. The portable toilet station of claim 1, wherein the heatingelement includes an electric coil.
 3. The portable toilet station ofclaim 2, the heating system including a blower assembly to direct heatedair in the direction of the holding tank.
 4. The portable toiletsatellite station of claim 1, wherein the heating pipe includes atransverse aperture positioned below the heating element for circulatingheated air into the inside area of the enclosure.
 5. The portable toiletstation of claim 1, the heating system having a temperature control unitoperatively connected with the heating element.
 6. The portable toiletstation of claim 5, wherein the temperature control unit has an outputheat sensor positioned to sense the temperature of heated air downstreamof the heating element.
 7. The portable toilet station of claim 1,further comprising a sink system having a sink, a water tankinterconnected to the sink and a drainage pipe interconnected to theholding tank; wherein the heating system can prevent water within thewater tank from freezing by warming the inside area.
 8. The portabletoilet station of claim 1, wherein the heating element is located insideof the heating pipe.
 9. An above-ground holding tank system for use witha restroom having a toilet, waste being transferred from the toilet tothe above-ground holding tank system, the above-ground holding tanksystem comprising: a holding tank having an aperture; and a heatingsystem in communication with the aperture, the heating system having aheating element, wherein the heating system directs warm air produced bythe heating element into the holding tank.
 10. The above-ground holdingtank system of claim 9, wherein the aperture is proximate a top surfaceof the holding tank.
 11. The above-ground holding tank system of claim9, further including a vent pipe to vent warm air within the holdingtank.